Merge pull request #136 from zaufi/master

New command runner: Jinja2 renderer
If there is an unknown token in Yaml expression, put its value in the exception string
Make sure that format_deep formats strings inside structures as mentioned in PR #136
Also allow literals in single quotes
Document a problem with expressions formed by just one literal
use mapping instead of list to pass params to jinja_render command
Merge branch 'master' of github.com:zaufi/devassistant